DTC Diagnosis Procedure

CHECK EXHAUST GAS LEAKAGE

Start engine and run it at idle.

Listen for an exhaust gas leakage before three way catalyst (manifold).

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Is exhaust gas leakage detected?

YES

Repair or replace malfunctioning part.

GO TO 2.

CHECK FOR INTAKE AIR LEAKAGE
1. Listen for an intake air leakage after the mass air flow sensor.
2. Check PCV hose connection.
Is intake air leakage detected?

YES

Repair or replace malfunctioning part.

NO

GO TO 3.

CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT

Turn ignition switch OFF.
Disconnect corresponding A/F sensor 1 harness connector.
Disconnect ECM harness connector.

Check the continuity between A/F sensor 1 harness connector and ECM harness connector.

A/F sensor 1		ECM		Continuity
Connector	Terminal	Connector	Terminal
F12	1	F25	86	Existed
	2		88

Check the continuity between A/F sensor 1 harness connector and ground, or ECM harness connector and ground.

A/F sensor 1		Ground	Continuity
Connector	Terminal
F12	1	Ground	Not existed
	2

ECM		--	Continuity
Connector	Terminal
F25	86	Ground	Not existed
	88

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

GO TO 4.

Repair or replace malfunctioning part.

CHECK FUEL PRESSURE

Install all removed parts.
Release fuel pressure to 0. Refer to Work Procedure .

Set a fuel pressure meter and check fuel pressure. Refer to Work Procedure .

At idle: 3, 000 kPa (30.6 kg/cm ² , 435 psi)

Is the inspection result normal?

YES

GO TO 6.

GO TO 5.

DETECT MALFUNCTIONING PART
Check fuel hoses and fuel tubes for clogging.

Is the inspection result normal?

YES

Replace "fuel filter and fuel pump assembly". Refer to Removal and Installation .

NO

Repair or replace malfunctioning part.

CHECK MASS AIR FLOW SENSOR

With CONSULT

Install all removed parts.
Start the engine and warm it up to normal operating temperature.

Check "MASS AIR FLOW SENSOR (Hz)" in "DATA MONITOR" mode of "ENGINE" using CONSULT.

Monitor item	Condition	Indication
MASS AIR FLOW SENSOR (Hz)	Ignition switch ON (Engine stopped.)	Approx. 3, 700 Hz
	Idle (Engine is warmed-up to normal operating temperature.)	Approx. 5, 500 Hz
	Idle to about 4, 000 RPM	5, 500 Hz -> 7, 000 Hz*

*: Check for linear frequency rise in response to increase of engine speed.

Without CONSULT

Install all removed parts.
Start the engine and warm it up to normal operating temperature.

Check the frequency between ECM harness connector terminals under the following conditions.

ECM			Condition	Frequency
Connector	+	-
	Terminal
F24	26	23	Ignition switch ON (Engine stopped.)	Approx. 3, 700 Hz
			Idle (Engine is warmed-up to normal operating temperature.)	Approx. 5, 500 Hz
			Idle to about 4, 000 RPM	5, 500 Hz -> 7, 000 Hz*

*: Check for linear frequency rise in response to increase of engine speed.

Is the inspection result normal?

YES

GO TO 7.

Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or grounds. Refer to DTC Diagnosis Procedure .

CHECK FUNCTION OF FUEL INJECTOR

With CONSULT

Start the engine.
Perform "POWER BALANCE" in "ACTIVE TEST" mode of "ENGINE" using CONSULT.
Check that each circuit produces a momentary engine speed drop.

Without CONSULT

Start the engine and let it idle.

Listen to each fuel injector operating sound.

Clicking sound should be heard.

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Is the inspection result normal?

YES

INSPECTION END

Perform trouble diagnosis for fuel injector and circuit, Refer to Diagnosis Procedure .